Stripper block machine



' I F. .J. STRAUB 4 STRIPPER- BLOCK MACHINE Filed Feb. 176, 1927 s Sheets-Sheet 1 Dec. 13, 1927. 1,652,381

- F. J. STRAUB Y I STRIPPER BLOCK MACHINE Filed Feb. 1 1927 v 3 Sheets-Sheet 2 1,652,381 F. J. STRAUB STRIPPER BLOCK MACHINE. l

Filed Feb. 16, 1927 1 5 Sheets- Sheet 3 H H l l 4 I 4 1 ,1111? ,LJflT /7 7 /7 /Z Mama Patented Dec. 13, 1927.

FRANCIS J. .s'rnAUn, on NEW xnnsinoron, rnnnsynvsnm,

s'rmrrnn BLOCKMAEGVHIN'E.

Application filed February 16, 1927. "Serial No. 168,567;

This invention relates to improvements in the manufacture .of hollow building material, as blocks, made from concrete aggregate. "It has for its object to provide means for imparting compressive action "to the aggregate within the mold and around :the usual cores, in connection with co -operating movement-of :the cores themselves, downwardly in compressing and then upwardly to a limited extent in ejecting or stripping, with a fina'lwiping action further movement of the block against the cores. Such operation effects a trowelling actionor movement not only between the inner mold surfaces and the outer wall of the block, but

also between the cores and the contacting or inner faces of the blocksurrounding the resulting coreopenings. 'It also'etlects a more even distribution and quality to the aggregate, due to the frictionaldevelopment of transverse forces through the aggregate tending to overcome voids, etc. p

The advantages of the invention reside in a more regular and compact disposition of the aggregate, preventing arching or objectionable openings, with even distribution,

together with a more economical application of power in performing the several operations, particularly'in ejecting.

In the drawings, showing one preferred embodiment of the invention:

"Fig. 1 is a plan view,showing one side of a molding machine, including a single block cavity,

Fig. 2 is a vetical sect'ional'view through the machine on the line"I'I--I'I of "Fig. 1, showing the mold filled and leveled and the presser plate elevated; I

Fig. 3 is a partial side elevation of Fig. 2; i

Fig. 4 is a' partial view, similar to Fig. 2, showing the presser plate lowered within the top of the mold and compressing the loose aggregate, and with the cores correspondingly lowered;

Fig. 5 is a similar view, showing the press; er plate removed, and thep-ressed block ele vated to the extent of return upward movement of'the cores;

Fig. 6 is a similar view, showing the finishedblock removed upwardly beyond 'the mold and its cores;

- Figs. 7 and 8 are diagrams showing the proportionate extent of trowel-ling action on the aggregate by frictionalaction of the mold faces and core faces respectively.

I The mold 20f the machine is mounted-on frame 3 and is provided with a vertically movable core bridge supporting the cores 5. A pressing plate '6 of standardconstruc tion is connected by cross bars 7 "with the outwardly swinging vertically movable side plates 8, of well known construction and opera-tiom'ifor imparting downward pressing actionon the aggregate.

In the construction shown, cross :bars 7 are provided with vertically arranged transverse temper screws 9 adjustably mounted in arm 7 and provided with securing lock nuts 10, whereby the thrust of screws 9 may be regulated and fixed.

As shown, the terminals of the screws 9 engage centralizing sockets in the tops of the cores, thereby avoiding any tendency ot-the coresto lateral movementunder pressure.

Core bridge l, instead of being fixedly held across underneath the mold as in usual construction, is slidably mounted on studs 11 tapped upwardly into the lower edges of the mold and extending downwardly t'hrouglithe iterminal edge portions of the core bridge, as shown. Studs 11 extend suf fici-ently far to provide ample range of movement of supporting springs 12 carried by lower lock nuts 13. s y

-Springs 12 are sufliciently strong to pro vide cushioning resistance for the core bridge and its cores on downward movement, and to re-ac't thereagainst for elevation of these parts upon suficient reduction of friction, as in ejecting the finished block.

That is to say, when the springs are compressed as in Fig. 4, and presser plate 6 is elevated, the springs are not sufiiciently strong to lift the core bridge and to thrust the cores upwardly because of friction until the finished block is correspondingly raised by suitable ejecting mechanism, as in Fig.

'Due to sueh internal friction against the cores, they will rise with the block at the commencement of the ejecting movement,

thereby reducing the initial necessary force.

Bottom plate '15 occupies its usual position in the lower portion of the mold, for

support of the usual bottom pallet 16, and

after pressing such bottom plate and pallet are elevated for removal, as is generally understood and practiced in machines of this kind.

lVith the machine constructed as above described, and with the cores 5 held upwardly in their normal erected position within the mold, as in Fig. 2, the mold cavity surrounding the cores is filled with 21g grog-ate flush to the top, the presser plate 6 being temporarily thrust out of the way latorally and then brought back for downward pressure. As the presser plate and its parts move downwardly, screws 9 come into contact with the upper ends of cores 5, so that, as the plate compresses the aggregate, the inner or intermediate cores 5 are correspondingly depressed, as shown in Fig. t.

Such action depresses the core bridge 4 correspondingly against its supporting springs 12, and at the same timeetfects an active trowelling movement against the main lower and middle portion of the aggregate, with increasingetfect towards the bottom, for the full extentof the stroke. Thereafter, the compression of the aggregate being completed, upward movement of the bottom plate 15 will eject the finished block in the usual way.

Frictional engagement between the inner faces of the block and the main cores 5 will hold them lowered, after the pre=ser plate 6 has been first ole ated and thrust out of the way laterally and relieving pressure on the cores by screws 9.

Thereafter, upward ejecting movement of the block will proceed until it and the cores have risen for the amount of spacing between the lowered core bridge and the bot tom of the mold, until it reaissumes its non mal position under action of springs 12, as in Fig. 5.

The cores 5 are restrained from further upward movement by their connection with the core bridge, as by stud bolts 17. Theretlftel',tll0 continued elevation of the block will effect further tro'welling action between the inner contacting surfaces and said cores, as well as against the endmost stationary cores, and likewise between the outer faces of the block and the inner faces of the mold, so that, when finally ejected, the block will be completely trowelled and finished, both inside and out.

In this way the conmicncement of the stripping action, which requiresthe greatest power, does not effect any frictional rubbing except between the outside of the block and the inside of the mold, by reason of the preliminary accompanying upward movement of the cores themselves.

Upon arresting of the cores, the upward movement having been started is easily continued until the block is finally ected. This stripping first against the outside surfaces and then against both outside and inside greatly reduces the required initial power for the stripping operation.

From the foregoing description, it will be observed that when the aggregate is pressed in the mold under lowering action of the presser plate, the compressive action thereof will be at its maximum at the top of the a"- gregate; that, as the presser plate descencfs, the downward movement of the particles of the aggregate will steadily decrease toward the bottom of the mass.

That is to say, the upper portion of the aggregate, during such compression or densilication, will descend within the mold at a corresponding rate of speed, i. e., with a maximum acceleration at the top, steadily diminishing toward the bottom, where the aggregate is resisted by the stationary pallet and bottom plate.

Likcwis that the trowelling action of the inner faces of the stationary mold and its endmost cores against the outer contacting faces of the aggregate will be effected in the same relatively diminishing ratio, due to the fact of the reducing rubbing action of the aggregate against the mold from its upper maximum activity toward the bottom, where the aggregate is inert.

Such action on the aggregate, varying -from maximum at the top to a minimum at the bottom, .is indicated by the arrows at the left side of Fig. 2.

On the other hand,.due to the lowering movement of the cores, iii conformity with the lowering of the presser plate, the cores will descend at a rate of speed equal to that of the descent of the presser plate and with a minimum trowelling action at the top, steadily increasing toward the bottom. This action is due to the fact that the speed of movement of the core in lowering is uniform throughout and its trowelling action is against the inner surfaces of the aggregate under compression, with the maximum of such compression and downward movcn'ient at the top, steadily diminishing toward the bottom. The relative rubbing action of the cores, therefore, due to the steadily diminishing downward movement of the aggregate itself, is proportionately and steadily increased toward the stationary bottom .of the aggregate as the cores descend.

These effects and the relative degree and extent of such compression and corresponding trowelling movement are illustrated in the diagrams of Figs. 7 and 8. These are for the purpose of showing the difference in the amount of trowelling action which the various portions of the block receive tliroughout its depth while it is being pressed, both outside and lnside. Thus, in

bill

ill?) lll lilt] dens.

ament gfiegate (a say ten ma s, aid dividing as block vertically into any arbitrary number ot equal i' erticalsections; as L, M,-N and 0, it will lie-observed that, asthe compression;

of theblock is'effected, its top portion will" be lowered with ar'n'a ximum' rubbi'i'i-g or compression movement and tro'x've'lling; ac-

. tion, again repeated in 'section N, while in section O, the trowelli'ng actio nsteadilydiifrinis'he's toward the bottom, where it is 0a the other had, use tO tllefact that g the downward niove'men t of the cores is co- 'eX teiis1 with the; eo'mpre'ssien movement of the" presser plate on the aggregate,- the realising trowe'll i ng action" the corein section-L an be reverse order, i. e., from zero t limited degree through section L, thenwith: a greater increase downwardly throngh section; M, a correspondingly greater increase through section N, and continuing increase through section 0, with i the maximum trowelling action at the bottom. Thisis, of course, because of the steadily decreasing speed of compressive movement of the particles of the block throughout. its depth during uniform downward travel of thecores and with a steadily increasing ratio of comparative frictional speed and resulting ,trowelling, compared to thesteadily decreasing compressive action.

Such effect, both as to the outside trowellingagainst the inner faceof the stationary mold and against the/relatively movable lowering cores, during compression, is indi-.

cated by the shaded" lines at the left side of Fig. 7 and right side of Fig.8 respectively.

As already describedfthe additional trowe elling action by the rubbing of the inside facesof the block against the arrested cores during upward, ejection is wholly supple mental and additional to such trowelling during downward movement of the presser plate. 7 In ordinary molding of aggregate blocks and the like within stationary molds and around stationary cores, the material res ceives its maximum pressure movement and trowelling action at the top,steadily decreasing towards none at all at thebottom. This 'resultsin great variation of consistency, the resulting product being non-uniform, with a tendency to voids, arches, and

unequal distribution towards and at the bottom. 7

By lowering the cores during compression their frictional'" or trowelling action is imparted laterally through the. aggregate in a proportion'increasing directly andsteadily in the direction of the steadily reducing .fIiOIH" p vtur 'e' of body portion' tl i rouig hotit, 'withchanges are to be understood as within compressivemovement of the aggregate it'- The increasing self,- towards the bottom. absence of such compressive movement towardsthe bottom is thus compensated for V and provided by the supplemental independent downward movement of the interior cores-during compression. 7

its-general effect, the rubbing or 'tro-'wcompletedisturbance' and settlement of; tire; ag regate throughoutits entire depth, so"

5 thae'voids' etoi, are eliminated. I g The m'xturie is more evenly distributed to bottom, with a more even ten} greater uniformity density dry;

D'iie-"toqsucl-i troweiling aetiong and the more even and better distribution of the aggregate, the surface finish otthe b'loc k both outside and inside, l is greatly improved; A turthec advantage, as above noted, is in: the easier manipulation of the machine, and better, distribution of the power applied.

The machine may be changed or varied in different details or in other respects by the skilled mechanic, toadapt it to varied conditions of use or otherwise, but all such the scope of the following claims. r

I \VhatI claim is: I 1. A concreteblock molding machine hav ing a mold, apresser plate, a bottom, and a movable core having a spring supported platform.

ing a mold, a presser plate, a'botto-m, and a vertically movable core having a spring supported platform. r

3. A concrete block molding machine having a mold, a pressure. plate, a bottom, and a vertically movable core provided with a fixedly connected transverse spring retracted support.

plate having-a portion adapted to' engage and depressthe core.

6. The combination with niold'hav'ing an inner supporting bottom and means for lift- 2. A concrete block molding machine hav- 7 ing the bottom to eject a pressed bloclnof a resiliently mounted core bridge, a coremounted on the core bridge extending up? ISU- wardly through the bottom Within the mold. and a presser plate having a portion adapted to engage and depress the core 7. The eonihination with a mold having aninner supporting bottom and means for lifting the bottom to eject a pressed block, of a resiliently mounted core bridge, acore mounted on the core bridge extending upwardly through the bottom within the mold, and a presser plate having an adjustable portion adapted to engage and depress the core.

S. The combination with a mold having an inner supporting bottom, of a core bridge extendingaeross underneath themold, supporting stems therefor extending tt'ronrthe mold through the core bridge provided with terminal adjusting nuts and supporting springs, a core mounted on and secured to the core bridge extending upwardly through the bottom within the inoh'h and a presser plate having a portion adapted to engage and depress the core.

9. The combination with a mold having an inner supporting bottom, of a resiliently mounted core bridge, aeore thereon extending upwardly within the mold, a Vertically movable frame provided with a presser plate operable downwardly Within the mold,

and a screw adjustably mounted in the frame adapted to engage and depress the ,core as the presser plate descends. a

10. In a molding machine of the elass described, the combination with an outer mold and an interior core, of means for compressin aggregate within the mold, and means oeiated with said means and em bodying adjustable core moving devieesfor core moving devices for simultaneously ap plyingrnbbing aetion to interior portions of the said contents whereby to assist distribution of the contents under pressure.

In testimony whereof I hereunto afiix my signature.

FRANCIS Jr STRAUB. 

